A bill to declare the Port of Houston Authority bridge over Greens Bayou, Texas to be for all purposes a "lawful bridge" as defined in "An Act to provide for the alteration of certain bridges over navigable waters of the United States, for the apportionment of the cost of such alterations between the United States and the owners of such bridges, and for other purposes" approved June 21, 1940 (33 U.S.C. 511 et seq.).